Update Readme.md

Author: Ducasse

.github/workflows/Readme.md

@@ -9,9 +9,9 @@ name: Book with Pillar
 
 on:
   push:
-    branches: [ main ]
+    branches: [ master ]
   pull_request:
-    branches: [ main ]
+    branches: [ master ]
   schedule:
     - cron:  '0 0 * * 0'
 
@@ -86,4 +86,4 @@ jobs:
           title: "Development Build"
           files: |
             artifacts/*.pdf
-```
+```